EP 0701352 A3 19980805 - Automatic adaptatioof prewarping for transmission over a non-linear channel
Title (en)
Automatic adaptatioof prewarping for transmission over a non-linear channel
Title (de)
Automatische Anpassung von Vorerzerrungen für Übertragung über nichtlineare Kanäle
Title (fr)
Adaptation automatique de prédistorsion pour la transmission sur canaux non-linéaires
Publication
Application
Priority
US 30471594 A 19940912
Abstract (en)
[origin: EP0701352A2] The present invention discloses an improvement over existing techniques for transmitting data over voice-band telephone channels by automatically adapting the amount of warping or compression that is applied to a sequence of signal points. A sequence of warped signal points, each of which is related to a respective signal point of a predetermined base constellation according to a warp function, is received in a decoder via a transmission channel having a non-linear component. After each of the received signal points is unwarped using substantially an inverse of the warp function, the average dispersions of the received inner and outer signal points about corresponding sequences of expected signal points are calculated. The difference between the average dispersion of the inner and outer points is then computed and used to update the amount of warping or compression in order to further minimize the effects of the channel non-linearity. The desired amount of warping is communicated to the transmitting encoder.
IPC 1-7
IPC 8 full level
H04L 5/12 (2006.01); H04L 27/34 (2006.01)
CPC (source: EP KR US)
H04L 27/34 (2013.01 - EP US); H04L 27/3422 (2013.01 - KR)
Citation (search report)
- [A] GB 2262867 A 19930630 - AMERICAN TELEPHONE & TELEGRAPH [US]
- [A] US 4291277 A 19810922 - DAVIS ROBERT C, et al
- [DA] EP 0533363 A2 19930324 - AMERICAN TELEPHONE & TELEGRAPH [US]
- [A] SALEH A A M ET AL: "ADAPTIVE LINEARIZATION OF POWER AMPLIFIERS IN DIGITAL RADIO SYSTEMS", BELL SYSTEM TECHNICAL JOURNAL, vol. 62, no. 4, PART 01, April 1983 (1983-04-01), pages 1019 - 1033, XP002028354
Designated contracting state (EPC)
DE ES FR GB IT
DOCDB simple family (publication)
EP 0701352 A2 19960313; EP 0701352 A3 19980805; CA 2154502 A1 19960313; CN 1127448 A 19960724; IL 115233 A0 19951231; JP H0897806 A 19960412; KR 960012860 A 19960420; MX 9503851 A 20030311; TW 246758 B 19950501; US 5481567 A 19960102
DOCDB simple family (application)
EP 95306061 A 19950830; CA 2154502 A 19950724; CN 95116546 A 19950911; IL 11523395 A 19950911; JP 25821795 A 19950912; KR 19950030163 A 19950911; MX 9503851 A 19950908; TW 83109805 A 19941022; US 30471594 A 19940912